Decrease Python release frequency

[Chriscbr]

We briefly had an issue where the python version of the construct-hub library was not able to published because we hit a 10GB upload limit for PyPI. Our actual packages are around 30MB, but we release so frequently that we hit the limit.

The pypi support README says:

Upload limits are generally denied for the following reasons: project makes nightly releases and/or is published frequently

In lieu of this, we should find a way to publish to python less often (perhaps on a daily or weekly basis), or disable publishing in the mean time.